This invention relates generally to exercise and rehabilitation systems and methods, and, more specifically, to a linear tracking isokinetic exerciser.
When the hip, thigh, knee or ankle are injured, rehabilitation includes increasing the range of motion of the affected joint as well as increasing muscle strength and endurance. It is also necessary to retrain normal gait characteristics, particularly with regard to symmetrical strength and movement of both limbs. Thus, physicians and physical therapist have become increasingly interested in multi-joint exercises that simulate the dynamics of actual limb movement.
U.S. Pat. No. 3,784,194 illustrates a known exercise device for bilaterally and reciprocally exercising a person's limbs. A person using the exerciser sits on an upright seat and places each of his or her feet through a loop of a pedal. The pedals are secured to a forward end of an L-shaped lever located on each side of the exerciser, and the levers are coupled to an actuator which isokinetically controls the motion of the levers. Although useful in many respects, the device lacks some desirable features. For example, the upright seat makes exercising awkward and inefficient. The reciprocating peddles move arcuately and therefore do not properly simulate the forces encountered during actual walking. Movement of one limb inherently causes a corresponding movement in the other limb, so the device cannot isolate and exercise a single limb at a time. Analog hydraulic pressure gauges are used to measure the forces generated by each leg, but the indirect nature of the measurement only approximates the actual force being applied to the pedals. The needles in the gauges are not damped, so they bounce severely under even moderate use. Thus, unless gross differences exist between limbs, the gauges do not provide sufficient information for adequate gait or strength training.